
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>照片墙一多实例演示（面向对象版）</title>
<style type="text/css">
body,div,h2,ul,li{margin:0;padding:0;}
body{font:12px/1.5 Arail;}
.box{width:860px;margin:10px auto;background:#eee;border:1px solid #b8b8b8;overflow:hidden}
.title{height:30px;line-height:30px;font-size:14px;padding:0 15px 0 35px;border-bottom:1px solid #b8b8b8;background:#fafafa url(img/ico.gif) 5px 50% no-repeat;}
.title span{float:left;}
.title a{float:right;color:#06f;outline:none;}
.title a:hover{color:red;}
.box ul{float:left;padding:0 15px 15px 0;}
.box li{float:left;width:140px;height:105px;padding:6px;background:#fff;border:1px solid #c3c3c3;display:inline;margin:15px 0 0 15px;list-style:none;}
.box li img{float:left;width:140px;height:105px;}
.box li.hig{padding:5px;border:2px dashed #f30;opacity:0.5;filter:alpha(opacity=50);}
</style>
<script type="text/javascript">
	//获取ID
	var $ = function (id) {return typeof id === "string" ? document.getElementById(id) : id};
	
	//获取tagName
	var $$ = function (tagName, oParent) {return (oParent || document).getElementsByTagName(tagName)};
	
	//获取class
	var $$$ = function (sClass, oParent) {
		var aClass = [],
		i = 0,
		reClass = new RegExp("(\\s|^)" + sClass + "($|\\s)"),
		aElement = $$("*", oParent);
		for (i = 0; i < aElement.length; i++)reClass.test(aElement[i].className) && aClass.push(aElement[i]);
		return aClass
	};
	
	//获取元素位置
	function getPos(obj) {
		var iTop = obj.offsetTop;
		var iLeft = obj.offsetLeft;
		while (obj.offsetParent)
		{
			iTop += obj.offsetParent.offsetTop;
			iLeft += obj.offsetParent.offsetLeft;
			obj = obj.offsetParent;
		}
		return {top:iTop, left:iLeft}	
	};
	
	//创建照片墙对象
	var PhotoWall = function () {this.initialize.apply(this, arguments)};
	
	PhotoWall.prototype = {
		initialize: function (obj, aData)
		{
			var oThis = this;
			this.oParent = $(obj);
			this.oUl = $$("ul", this.oParent)[0];
			this.oBtn = $$("a", this.oParent)[0];
			this.zIndex = 1;
			this.aPos = [];
			this.aData = aData;
			this.dom = document.documentElement || document.body;
			this.create();
			this.oBtn.onclick = function () {oThis.randomOrder()}
		},
		create: function ()
		{
			var aFrag = document.createDocumentFragment();
			var i = 0;
			for (i = 0; i < this.aData.length; i++)
			{
				var oLi = document.createElement("li");
				var oImg = document.createElement("img");
				oImg.src = this.aData[i];
				oLi.appendChild(oImg);
				aFrag.appendChild(oLi)	
			}
			this.oUl.appendChild(aFrag);
			this.aLi = $$("li", this.oParent);
			this.changeLayout()
		},
		changeLayout: function ()
		{
			var i = 0;
			this.oParent.style.height = this.oParent.offsetHeight - 2 + "px";
			this.aPos.length = 0;
			for (i = 0; i < this.aLi.length; i++) this.aLi[i].style.cssText = "";	
			for (i = 0; i < this.aLi.length; i++)
			{
				this.aLi[i].index = i;
				this.aLi[i].style.top = getPos(this.aLi[i]).top + "px";
				this.aLi[i].style.left = getPos(this.aLi[i]).left + "px";
				this.aPos.push({left:getPos(this.aLi[i]).left, top:getPos(this.aLi[i]).top})
			}
			for (i = 0; i < this.aLi.length; i++)
			{
				this.aLi[i].style.position = "absolute";	
				this.aLi[i].style.margin = "0";			
				this.drag(this.aLi[i])
			}	
		},
		drag: function (obj, handle)
		{
			var oThis = this;
			var handle = handle || obj;
			handle.style.cursor = "move";
			handle.onmousedown = function (event)
			{
				var event = event || window.event;	
				var disX = event.clientX - this.offsetLeft;
				var disY = event.clientY - this.offsetTop;
				var oNear = null;
				handle.style.zIndex = oThis.zIndex++;
				
				document.onmousemove = function (event)
				{
					var event = event || window.event;
					var iL = event.clientX - disX;
					var iT = event.clientY - disY;
					var maxL = Math.max(oThis.dom.clientWidth, oThis.dom.scrollWidth) - handle.offsetWidth;
					var maxT = Math.max(oThis.dom.clientHeight, oThis.dom.scrollHeight) - handle.offsetHeight;
					
					iL < 0 && (iL = 0);
					iT < 0 && (iT = 0);
					iL > maxL && (iL = maxL);
					iT > maxT && (iT = maxT);
								
					handle.style.left = iL + "px";
					handle.style.top = iT + "px";
					
					oNear = oThis.findNearest(obj);
					
					for (var i = 0; i < oThis.aLi.length; i++) oThis.aLi[i].className = "";
					
					oNear && (oNear.className = "hig");
					
					return false
				};
				document.onmouseup = function ()
				{
					document.onmousemove = null;
					document.onmouseup = null;
					
					if (oNear)
					{
						handle.index = [handle.index, oNear.index];
						oNear.index = handle.index[0];
						handle.index = handle.index[1];
						oNear.style.zIndex = oThis.zIndex++;
						oThis.doMove(handle, oThis.aPos[handle.index]);
						oThis.doMove(oNear, oThis.aPos[oNear.index]);					
						oNear.className = "";
					}
					else
					{
						oThis.doMove(handle, oThis.aPos[handle.index])	
					}
					
					handle.releaseCapture && handle.releaseCapture()
				};
				this.setCapture && this.setCapture();
				return false
			};
		},
		doMove: function (obj, iTarget, callback)
		{
			var oThis = this;
			clearInterval(obj.timer);
			obj.timer = setInterval(function ()
			{
				var iCurL = getPos(obj).left;
				var iCurT = getPos(obj).top;
				var iSpeedL = (iTarget.left - iCurL) / 5;
				var iSpeedT = (iTarget.top - iCurT) / 5;
				iSpeedL = iSpeedL > 0 ? Math.ceil(iSpeedL) : Math.floor(iSpeedL);
				iSpeedT = iSpeedT > 0 ? Math.ceil(iSpeedT) : Math.floor(iSpeedT);
				
				if (iCurL == iTarget.left && iCurT == iTarget.top)
				{
					clearInterval(obj.timer);
					callback && callback()	
				}
				else
				{
					obj.style.left = iCurL + iSpeedL + "px";
					obj.style.top = iCurT + iSpeedT + "px"	
				}
			}, 30)
		},
		findNearest: function (obj)
		{
			var aDistance = [];
			var i = 0;
			for (i = 0; i < this.aLi.length; i++) aDistance[i] = this.aLi[i] == obj ? Number.MAX_VALUE : this.getDistance(obj, this.aLi[i]);
			
			var minNum = Number.MAX_VALUE;
			var minIndex = -1;
			for (i = 0; i < aDistance.length; i++) aDistance[i] < minNum && (minNum = aDistance[i], minIndex = i);
			
			return this.isButt(obj, this.aLi[minIndex]) ? this.aLi[minIndex] : null
		},
		getDistance: function(obj1, obj2)
		{
			var a = (obj1.offsetLeft + obj1.offsetWidth / 2) - (obj2.offsetLeft + obj2.offsetWidth / 2);
			var b = (obj1.offsetTop + obj1.offsetTop / 2) - (obj2.offsetTop + obj2.offsetTop / 2);
			return Math.sqrt(a * a + b * b)
		},
		isButt: function (obj1, obj2)
		{
			var l1 = obj1.offsetLeft;
			var t1 = obj1.offsetTop;
			var r1 = l1 + obj1.offsetWidth;
			var b1 = t1 + obj1.offsetHeight;
			
			var l2 = obj2.offsetLeft;
			var t2 = obj2.offsetTop;
			var r2 = l2 + obj2.offsetWidth;
			var b2 = t2 + obj2.offsetHeight;
			
			return !(r1 < l2 || b1 < t2 || r2 < l1 || b2 < t1)
		},
		randomOrder: function ()
		{
			this.aPos.sort(function () {return Math.random() > 0.5 ? 1 : -1});
			for (var i = 0; i < this.aLi.length; i++)
			{
				this.aLi[i].index = i;
				this.doMove(this.aLi[i], this.aPos[i])
			}
		}
	};
	window.onload = function ()
	{
		var aBox = $$$("box");
		var aData = [];
		var aExample = [];
		var i = 0;
		//生成图片数据
		for (i = 0; i < 20; i++) aData[aData.length] = "img/" + i + ".jpg";
		//循环创建多个实例
		for (i = 0; i < aBox.length; i++)
		{
			var oExample = new PhotoWall(aBox[i], aData);
			aExample.push(oExample)
		}
		this.onresize = function ()
		{
			for (var p in aExample) aExample[p].changeLayout()	
		};
		this.onresize()
	};
</script>
</head>
<body>
	<div class="box">
	    <h2 class="title"><span>一堆90后</span><a href="javascript:;" class="order">随机排序</a></h2>
	    <ul></ul>
	</div>
	<div class="box">
	    <h2 class="title"><span>一堆90后</span><a href="javascript:;" class="order">随机排序</a></h2>
	    <ul></ul>
	</div>
</body>
</html>
